Virtual moveable endcap non-reversing heater chiller system

ABSTRACT

The invention sets out a system of interconnected non-reversing heater-chiller modules having a virtual moveable endcap separating select units. The system facilitates the variable operation of heater/chiller modules in a combination of heating/chilling/simultaneous operation modes, or rest modes, in order to adjust to variable building load, mechanical, and environmental conditions.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to improvements in heating and cooling systems.Particularly, the invention relates to a plurality of modularheater/chiller units which are arranged to provide greater flexibilitymeeting heating and cooling demands while at the same time reducingenergy consumption.

The present invention utilizes a plurality of heater/chillers which areinterconnected and controlled in a manner which allows for optimalutilization of condenser-heat and evaporator cooling during full timeheating, full time cooling, and variable simultaneous heating/coolingload applications.

2. Description of the Related Art

In the past, there have been efforts to provide coordinated multipleunit chiller/heater structures and systems to provide flexibility inmeeting heating/cooling requirements while at the same time reducingenergy consumption.

See for example US Patent Application Publication US 2010/0132390 A1.

However, although these systems provide a substantial advantage over theprior art, they still suffer from certain shortcomings. For example, theprevious virtual moveable endcap systems involved the use of reversingheat pump chillers, with the inherent individual efficiency compromises,drawbacks and reversing problems. Also in some arrangements, the unitson each end of the arrangement tended to experience more wear and tearthan the center units with a resultant imbalance in the reliability andmaintenance of the system as a whole.

It is therefore desirable to provide a virtual moveable endcapheating/cooling system which avoids the efficiency shortcomings ofreversing heat pump/chiller systems.

It is desirable to provide a virtual moveable endcap heating/coolingsystem which allows for even distribution of wear and tear on theindividual units.

It is desirable to provide a virtual moveable endcap heating/coolingsystem which utilizes a ground or water source heat sink for storage andexchange of heat.

It is also desirable to provide a virtual moveable endcapheating/cooling system which allows for full flexibility in utilizingall or one of the individual units, or any combination of units, tovariably provide heating, cooling, or a combination of simultaneousheating and cooling, variable depending on changing building loadrequirements, ambient conditions, mechanical considerations andelectrical energy costs.

BRIEF SUMMARY OF THE INVENTION

According to the present invention, there is provided a heating/coolingsystem comprising a plurality of modular non-reversing heater/chillerunits. Each module unit may comprise one or more compressors, a workingfluid loop, an evaporator, a condenser, cooling load fluid connections,heating load fluid connections, and virtual moveable endcap connectionsat each side or alternatively one side of both the cooling load andheating load fluid connections. The connections may most preferably beeasily separable and reconnectable, such as compression fittings, or maybe more conventional connections such as flanged, screwed, or evenwelded connections. The virtual moveable endcap connections may eachinclude a valve to isolate flow.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS

FIG. 1 shows modular units with 1 through n heating side and 1 through ncooling side applied to building load, here n=6

FIG. 2 shows modular units with 1 through n cooling side applied tobuilding load and 1 through n heating side sending heat to sink

FIG. 3 shows modular units with 1 through n heating side and 1 through(n−1) cooling side applied to building load, and n cooling sidereceiving heat from sink

FIG. 4 shows modular unit 1 heating side and 1 through n cooling sideapplied to building load, and (n−4) through n heating side sending heatto sink

FIG. 5 shows modular units with 1 through n heating side and 1 through ncooling side applied to building load, where unit n+5 is rested

FIG. 6 shows modular units with 1 through n heating side and 1 through ncooling side applied to building load, where unit n+2 is rested

DETAILED DESCRIPTION OF THE INVENTION

Following is a list setting out various elements of the invention asdescribed in the foregoing drawing Figures.

1. Building

2. Building Cooling Heat Exchanger

3. Building Heating Heat Exchanger

4. Modular Non-reversing Chiller Heater

5. Condenser

6. Evaporator

7. Working Fluid Loop

8. Heat Sink/Source

9. Heat Sink/Source Comingled Heat Exchanger

10. Heat Sink/Source Hot Side Heat Exchanger

11. Heat Sink/Source Cold Side Heat Exchanger

12. Evaporator Control/Isolation Valve

13. Condenser Control/Isolation Valve

14. Building Conditioning Fluid Conduit

15. Virtual Moveable Endcap Valve

16. Comingled Heat Sink/Source Hot Side Isolation Valve

17. Comingled Heat Sink/Source Cold Side Isolation Valve

18. Heat Sink/Source Local Hot Side Heat Exchanger Valve

19. Heat Sink/Source Local Cold Side Heat Exchanger Valve

There are four main states or modes for each of the individual modularunits, as set out below:

Evaporator Condenser Operation Operation State 1 cool building spacereject heat to sink/source State 2 cool building space utilize heat inbuilding space State 3 receiving heat from sink/source utilize heat inbuilding space State 4 off (rest or repair) off (rest or repair)

The number of permutations and combinations of these four useful statesof each modular unit, when combined into a system of modular units canbe mathematically determined.

Where n=number of individual modules in a system, each module beingnumbered 1 through n. Then the total number of possible permutations andcombinations of the various arrangements of cooling/heating/heat sinksource/off operation modes for the entire system is given by therelation:

Number of possible modes=4^(n).

There may be practical considerations which would tend to reduce themaximum number of possible mathematical modes.

The possibility of utilizing the condensers and evaporators of eachmodular unit selectively in different modes, provides for flexibilityheretofore not seen in heating/cooling systems.

This flexibility allows the operator to continually select the mostefficient operating mode for even rapidly changing buildingload/ambient/electricity cost conditions.

Another major advantage of the present invention is that any or all ofthe individual units may be rested as necessary. The operating loadfactor on the mechanical equipment of each unit can be preciselymonitored and balanced. End units, middle units, or any combination canbe selectively rested. This will result statistically in the longestlife span possible for the entire system without the need for shutdowndue to failure of an overworked unit. Meanwhile, should a failure occurin any of the units, that unit may be removed from service while stillmaintaining a remarkable level of performance and flexibility in thesystem as a whole utilizing the remaining units.

Another advantage of the present invention is that all modular units arenon-reversing, with the resultant inherent efficiencies available innon-reversing chillers. In contrast, prior art reversing heat pumpssuffer from inherent operating efficiency drawbacks, owing in part tothe fact that elements of the equipment must be compromised, due to thereversing nature of the machine.

Referring now to the drawings:

In FIG. 1 it is shown where units 1-n (n being 6 in this embodiment) areutilized where all heat for all condensers 5 is being utilized in thebuilding to be conditioned, while all cooling equipment from allevaporators 6 is simultaneously being utilized in the building. No heatis exchanged in the heat sink/source.

It is to be noted that modular element 1 in the drawings shows detailsincluding the evaporator/condenser isolation valves, and flow arrows,which point at the counter flow nature of the heat exchangers in oneembodiment. It is to be noted that these details are included in 2-nmodular elements, but are omitted from the drawing figures for the sakeof clarity in the figures.

In FIG. 2, it is shown where all heat from all condensers 1-n is beingrejected to the heat sink/source, while all cooling capacity from allevaporators 1-n is being utilized in the building.

In FIG. 3, it is shown where all heat from all condensers 1-n is beingutilized in the buildings, all cooling capacity from evaporators number1, 2, 3, 4, and 5 is being utilized in the building, while heat isexchanged between evaporator number 6 and the heat sink/source.

In FIG. 4, it is shown where heat from condenser number 1 is beingutilized in the building, heat from condenser numbers 2-6 is beingrejected to the heat sink/source, and all cooling capacity fromevaporators numbers 1-6 is being utilized in the building.

In FIG. 5, it is shown where modular unit 6 is taken out of service,while meanwhile all heat from condensers numbers 1-5 is utilized in thebuildings, and all cooling capacity from evaporators number 1-5 isutilized in the building. It must be noted that even with the unit 6 outof service a particular number of remaining condensers numbers 1-5 maybe selected to either provide heat to the building or reject heat to thesink/source, and a particular number of remaining evaporator numbers 1-5may be selected, independent from the utilization of the condensers, toeither provide cooling to the building or exchange heat with thesink/source.

In FIG. 6 it is shown where modular unit 3 is taken out of service whilemeanwhile all heat from condenser numbers 1, 2, 4, 5, and 6 is utilizedin the building, and all cooling capacity from evaporators numbered 1,2, 4, 5, and 6 is utilized in the building.

In FIG. 7 it is shown where modular units 2 and 5 are taken out ofservice. Meanwhile all heat from condensers 1, 3, 4, is utilized in thebuilding, all heat from condenser number 6 is rejected to the heatsink/source, all cooling capacity from evaporator numbers 1 and 3 areutilized in the building, and heat is exchanged between evaporatornumbers 4 and 6 with the heat sink/source.

The building/heat sink source conditions which would prompt such anoperating arrangement such as set out in FIG. 7 is not described forthis embodiment. This combination is set out merely to illustrate theflexibility in the present system.

In the foregoing examples, it may be that comingled heat sink/source hotside isolations valves 16 are open, comingled heat sink/source cold sideisolation valves 17 are open, heat sink/source local hot side heatexchange valves 18 are closed, and heat sink/source local cold side heatexchange valves 19 are closed. This valving arrangement could causecomingling of building conditioning fluid, and eventual heat exchange atheat sink/source comingled heat exchanger 9.

In one embodiment, heat sink/source hot side heat exchanger 10 andassociated valves 18 and heat sink/source cold side heat exchanger 11and associated valves 19 are provided at different locations in the heatsink/source. In this manner, the heat added and/or removed from the heatsink/source can be concentrated and adjusted locally depending on therequirements and capacities of the entire heat sink/source. In thisembodiment the building conditioning fluid can be kept separate, hotside and cold side, as it is sent into the heat sink/source.

It is contemplated that frequently, however, the building conditioningfluid will be comingled and sent to/from the heat sink/source in acomingled manner.

In this invention, in the preferred embodiment, there is only a single“refrigerant lift,” which allows for increased efficiencies of up to 30%and more over systems which do not operate with a single lift.

The virtual moveable endcap valves may be omitted between constantsimultaneous load modules, in certain embodiments, in the eventequipment cost savings are desired.

In certain embodiments, the modular elements have a single pointelectrical connection for valves and controllers, and may have adisconnecting circuit breaker for each module.

Modulating valves may be included for built-in head control and forprecisely controlling water temperatures.

Built-in heat recovery may result in simultaneous efficiency.

The compressors in the modular system can be run and rested wheredesired in a manner which results in equalization of their run times.

1. A building space heating and cooling system, comprising: a buildingspace to be conditioned, a heat sink/source, at least two modularnon-reversing heater chillers connected in parallel, each of saidnon-reversing heater chillers having a condenser, an evaporator, acondenser control/isolation valve, and an evaporator control/isolationvalve, a building conditioning fluid conduct containing buildingconditioning fluid, said building conditioning fluid conduct being inheat transfer connection with the evaporators, the condensers, said heatsink/source, a building space cooling side heat exchanger, and abuilding space heating side heat exchanger, virtual moveable endcapvalves disposed in said building conditioning fluid conduct to variouslyisolate or communicate heat transferred out of said condensers and heattransferred into said evaporators with said building conditioning fluid,wherein each of said modular non-reversing heater chillers can beselectively operated to send heat transferred from its respectivecondenser to said building conditioning fluid either to said buildingspace heating side heat exchanger or to said heat sink/source, and tosend building conditioning fluid having heat removed from it by saidrespective evaporator either to said building space cooling side heatexchanger or to said heat sink/source.
 2. A building space heating andcooling system, according to claim 1, comprising a plurality of modularnon-reversing heater chillers numbered 1-n connected in parallel, saidmodular non-reversing heater chillers having said respective condensersnumbered 1-n and said respective evaporators numbered 1-n, saidrespective condensers and evaporators being selectively separable viasaid virtual moveable endcap valves such that any or all of saidcondensers 1-n and any or all of said evaporators 1-n may be selectivelyisolated from said building space heating side heat exchanger and saidbuilding space cooling side heat exchanger respectively, and said heatsink/source.